All-Fiber Tunable Mmi Fiber Laser


EDFL; Erbium doped; Fiber laser; Fiber ring laser; MMI; Multimode interference; Tunable laser; Wavelength tunable laser; Widely tunable laser


We report on a novel tuning mechanism to fabricate an all-fiber tunable laser based on multimode interference (MMI) effects. It is well known that the wavelength response of MMI devices exhibits a linear dependence when the length of the multimode fiber (MMF) section. Therefore, tuning in the MMI filter is achieved using a ferrule (capillary tube of 127 μm diameter) filled with a liquid with a higher refractive index than that of the ferrule, which creates a variable liquid MMF. This liquid MMF is used to increase the effective length of the MMI filter and tuning takes place. Using this simple scheme, a tuning range of 30 nm was easily achieved, with very small insertion losses. The filter was tested within a typical Erbium doped fiber (EDF) ring laser cavity, and a tunable EDF laser covering the full C-band was demonstrated. The advantage of our laser is of course the simplicity of the tunable MMI filter, which results in an inexpensive tunable fiber laser. ©2009 SPIE.

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Proceedings of SPIE - The International Society for Optical Engineering



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Article; Proceedings Paper

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69749105643 (Scopus)

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